Abstract: A board of lumber containing a defect, such as a knot, is repaired by cutting an opening between major surfaces of the board and filling the opening with a plug of adhesive filler material or a wood plug which is adhered to the wall of the opening. The opening and plug are formed to have a non-circular shape. This facilitates re-sawing of the board to form two thinner boards as the shape of the plug prevents it from being loosened by turning forces created by the saw blade which is used to effect the re-sawing operation. In some of the repair configurations, portions of the plug which remain in both of the thinner boards following re-sawing also cannot be dislodged by external forces exerted against the surfaces of the board.

Abstract: Defects in wooden boards, such as knots, knotholes or cracks, are repaired by forming an opening in the board at the site of the defect and forming a plug that fills the opening. In some forms of the invention the opening has a shape which interlocks the plug to the board. In another form of the invention, the plug is held in place by a transversely extending resilient member that is embedded in the plug and which is under tension which causes edge portions of the member to bite into or bear against the adjacent wood. Forming the opening includes cutting away bark encasement tissue that may adjoin the defect which encasement can cause a discoloration upon painting of the board and may eventually loosen. In some forms of the invention, cracks are repaired by making plural saw cuts along a crack to form the opening with the saw having a different angling relative to the board during each saw cut.

Abstract: Boards of lumber or similar material having knotholes or other defects in an edge region are repaired by cutting an opening in the edge region to remove the defect and by filling the opening with a conforming plug formed of hardened mastic or of pieces of solid material which are adhered together. The opening extends inward from the edge of the board and is of greater extent at a location spaced inward from the edge than it is at another location that is closer to the edge. The expanse of the opening preferably increases at a first depth within the board and decreases at a second depth within the board. The configuration of the opening interlocks the conforming plug into the board thereby preventing ejection of the plug.

Abstract: Boards of lumber or the like which exhibit defects such as knots or knotholes are repaired by cutting a bore through the board at the site of the defect and by filling the bore with a plug of conforming shape. The width of the bore changes at a first location along its axis and undergoes a reverse change at another location in order to interlock the plug with the board. The plug may be formed by filling the bore with hardenable mastic or by fitting conforming pieces of wood or the like into opposite ends of the bore, the pieces being abutted and secured together by adhesive. The interlocking configuration of the bore and plug assures that the plug cannot be ejected from the board.